MANUFACTURE OF SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PURPOSE:To contrive a reduction in the capacity of the base and to realize the higher- speed operation of a semiconductor integrated circuit device and a reduction in the power consumption of the device by a method wherein the peripheral part of the island is coated with an oxide film and the base region is formed in the island region. CONSTITUTION:An Si layer at the bottom face part of each isolated groove 17 is removed as deep as the prescribed depth by a chemical etching method using a first Si3N4 film 15 and a second Si3N4 film 18 of the groove 17 as masks. A selective oxidation is performed using the first Si3N4 film 15 and the second Si3N4 films 18 as masks and isolated oxide films 10 are formed. The oxidation progresses in the directions of the bottom face and the side face and bottom face parts 19 in the vicinity of the island region are oxidized. The upper part of each groove 17 is filled with an SiO2 film 20 using an etchback method, a bias sputtering method and so forth. A P type active base region 12, P type inactive base contact regions 12', an N<+> type emitter region 13 and an N<+> type collector region 14 are formed by the ordinary method. Since the peripheral parts 12' of the base region 12 are being covered with the oxide film, the capacity between the base and the collector is remarkably reduced even though the base contact regions 12' are sufficiently taken widely.